1. Field of the Invention
This invention relates to an awning and more particularly to an awning with a canvas shaft and at least one holder for fastening the awning to a wall or a ceiling.
2. Discussion of Relevant Art
For example, an awning of this type is available on the market under the name Discus Vertikal (trade name of the company Lohausen). A similar awning is described in DE-A1 4103474.
Known awnings, corresponding to the precharacterizing clauses mentioned, have proved in practice to be stable, narrow or integrated awnings. The use of such awnings generally presents no problems but various customers required smaller but more efficient awnings (area of the extendable awning canvas in relation to the volume of the awning box as large as possible).
The Applicant, as patent proprietor, has become aware of a number of patents in this area and it is intended to outline below the development which led to the prior art used, so that it will be clear just how valuable is the invention described below.
DE-C-2909306 describes an awning which, under the trade name "Superflach", as a speciality compared with the prior art known at the time, has a rectangular mounting tube which was arranged in approximately a horizontal plane with the canvas shaft axis and, as a support element, held bearing blocks, swivel arms and the like. Since the mounting tube was practically held at its two ends by wall holders or support arms which projected from wall holders, there was a certain limit to the length of the mounting tubes (sag) and a limit to the width of the awning. Furthermore, such an awning was relatively deep since, owing to its spatial extension and owing to the space required by the bearing blocks, holders and the like mounted thereon, the mounting tube increased the depth of the total structure with wall holder, canvas shaft and swivel arms.
In comparison, in the novel design the depth is to be reduced and the flexural strength of the awning structure is to be improved to counteract sagging, so that larger awning widths are possible.
DE-C-3001919 has already attempted to reduce the depth and has created support elements which, in terms of the function, approximately corresponded to an above-mentioned mounting tube but reduced the depth compared with the "Superflach" awning. The support element, which projects upward as a narrow central web in front of the canvas shaft and over the total height of the latter and is fastened to support arms which grip under the canvas shaft, is however not as torsionally rigid as the known mounting tube, so that undesired torsional loads might occur on the support element in the case of relatively large awning lengths and widths. In addition, it is fairly complicated to fasten bearing blocks or the like to the narrow central web without further weakening said bearing blocks or the like by holes or the like.
In contrast, in the novel design the torsional rigidity is to be increased and the possibility of fastening further components of the awning is to be simplified. DE-C-3708155 describes a reinforcing profile which is connected to a central support element, comparable with the design last described, and thus improves its torsional rigidity. At the same time, guide strips are formed on the reinforcing profile in this structure and are intended for holding profile parts which can be pushed therein and on which bearing blocks and the like can then be fastened. Although this known design thus has good stability, it also has a large number of additional components which complicate the mounting of the awning and furthermore require an increased production effort.
In contrast, the awning according to the invention should require fewer components but nevertheless have a simple mounting facility for bearing blocks or the like without impairing the torsional rigidity and flexural strength.
An awning structure described in DE-A-4308965 has a hollow chamber structure for holding bearing blocks and canvas shaft. However, as a result of its design, it has a relatively small horizontal flexural strength, so that its lateral length is limited. This known structure furthermore has a disadvantage in mounting: when the canvas shaft is installed, it must be held by the mounting personnel until it has been mounted in its lateral bearing points. If this is not done, it may slide out of the awning box. During mounting, several fitters or additional securing measures are therefore required.
A more recent awning design--published in WO92/14009--which is comparable with the awning first described and forming part of the prior art and which offers a practical fastening facility for bearing blocks or the like and occupies a smaller depth than the original mounting tube design has been developed by the Applicant. However, the advantage of the universal applicability of this mounting tube is accompanied by the disadvantage that it must have a certain strength which depends on the highest requirements in each case, so that with lower requirements, for example for an awning having a relatively narrow awning canvas, an excessively dimensioned mounting tube and therefore, in such a case, an unnecessary size of the total awning are present.
In contrast, less universality but instead a better degree of integratability and a smaller size are required for the design according to the invention.